We have developed methods for analyzing both organic solvent extractable and a major portion of the water-soluble metabolites formed from polycyclic aromatic hydrocarbons by hamster embryo cell cultures. With both a methyl-substituted hyrocarbon, 7,12-dimethylbenz(a)anthracene, and an unsubstituted hydrocarbon, benzo(a)pyrene, the major organic solvent extractable metabolites are dihydrodiols and a major portion of the water-soluble metabolites are glucuronic acid conjugates of hydrocarbon phenols. We are presently using the methods developed for the studies described above, organic solvent extraction, cleavage of water-soluble metabolites with Beta-glucuronidase and high-pressure liquid chromatography, to determine the effect of cocarcinogens such as benzo(e)pyrene and tumor promoters such as 12-O-tetradecanoylphorbol-13-acetate on the pathways of metabolism of both methyl-substituted and unsubstituted hydrocarbons in hamster embryo cell cultures. The effects of these modifiers on the DNA adducts formed from carcinogenic hydrocarbons in hamster embryo cells are also being determined.